import duty on ebay items?

I've been after getting a boot lid lip spoiler (like one fitted to e46 M3) and have seen them on ebay, ones from uk are selling for about £75 but i've seen them from poland and germany for less than £25 and pre sprayed. but i've also read somewhere that there is a hidden import duty to pay on items that are shipped in from abroad?
so really 2 questions, is this true about the hidden duty?
and are these cheaper ones anygood? they look ok in the pictures.

Hi Bobby,

I import a fair bit of camera equipment from abroad and 8 times out of 10 will get charged import duty. The duties I have been charged has never been more than 17.5% (ie,VAT), more often than not its less, usually around 12%. I can't seem to figure out a rate calculation guide, but I've done it many times and its about this rate. Buying internationally on e-bay is ok, I've had no bad experiences - it's made easier if your seller accepts paypal or similar so no mucking about at banks doing transfers. My advice would be to look where there is a good exchange rate, just now buying from the USA is a dream. even if the item is more expensive you could save due to the dollar rate. Paypal give pretty good exchange rates.

Hope this helps,

Nick